Do you have an EVGA card?  If not, which make and model?
 
I have an NVIDIA made founders edition 1080ti, and it only shows 1 fan.  Mine seems correct.  Low values at idle + auto speed, shifts when I slide the fan slider and press apply button.  Pressing the ICX button on the right doesn't help me (I don't have an EVGA ICX card either :P), with the fan speed value disappearing from the left.
 
I think some fan speeds can't be read correctly when they run too slow.  And I assume you know if the fan(s) is stopping when it says 0 RPM/0 %.  Meaning maybe it's making so little heat you don't need a fan?  Would make the card extra quiet when running idle.  I don't know that card.